When an Interceptor is marshaled for an external (non-chrome) process caller, we do not provide a handler and thus don't call HandlerProvider::WriteHandlerPayload.
However, GetMarshalSizeMax previously called HandlerProvider::GetPayloadSize even for external process callers.
For a11y's handlerProvider, we must build the payload to get the size.
This is wasteful in this case, since we're just going to throw it away.
Differential Revision: https://phabricator.services.mozilla.com/D72796
When marshaling a11y calls from the content process, there are quite a lot of cross-thread QueryInterface calls (ipc::mscom::Interceptor::QueryInterfaceTarget).
Some of these are for special COM interfaces like IAgileObject and IFastRundown, which we could just special case in Interceptor::QueryInterface like we do for INoMarshal.
However, it seems there are a lot of other interfaces being queried and it's not clear why.
This patch adds a new HandlerProvider method: IsInterfaceMaybeSupported.
This allows implementations to indicate when there are interfaces which they definitely don't support, allowing the call to be answered without a cross-thread call.
Differential Revision: https://phabricator.services.mozilla.com/D69285
--HG--
extra : moz-landing-system : lando
This was done by:
This was done by applying:
```
diff --git a/python/mozbuild/mozbuild/code-analysis/mach_commands.py b/python/mozbuild/mozbuild/code-analysis/mach_commands.py
index 789affde7bbf..fe33c4c7d4d1 100644
--- a/python/mozbuild/mozbuild/code-analysis/mach_commands.py
+++ b/python/mozbuild/mozbuild/code-analysis/mach_commands.py
@@ -2007,7 +2007,7 @@ class StaticAnalysis(MachCommandBase):
from subprocess import Popen, PIPE, check_output, CalledProcessError
diff_process = Popen(self._get_clang_format_diff_command(commit), stdout=PIPE)
- args = [sys.executable, clang_format_diff, "-p1", "-binary=%s" % clang_format]
+ args = [sys.executable, clang_format_diff, "-p1", "-binary=%s" % clang_format, '-sort-includes']
if not output_file:
args.append("-i")
```
Then running `./mach clang-format -c <commit-hash>`
Then undoing that patch.
Then running check_spidermonkey_style.py --fixup
Then running `./mach clang-format`
I had to fix four things:
* I needed to move <utility> back down in GuardObjects.h because I was hitting
obscure problems with our system include wrappers like this:
0:03.94 /usr/include/stdlib.h:550:14: error: exception specification in declaration does not match previous declaration
0:03.94 extern void *realloc (void *__ptr, size_t __size)
0:03.94 ^
0:03.94 /home/emilio/src/moz/gecko-2/obj-debug/dist/include/malloc_decls.h:53:1: note: previous declaration is here
0:03.94 MALLOC_DECL(realloc, void*, void*, size_t)
0:03.94 ^
0:03.94 /home/emilio/src/moz/gecko-2/obj-debug/dist/include/mozilla/mozalloc.h:22:32: note: expanded from macro 'MALLOC_DECL'
0:03.94 MOZ_MEMORY_API return_type name##_impl(__VA_ARGS__);
0:03.94 ^
0:03.94 <scratch space>:178:1: note: expanded from here
0:03.94 realloc_impl
0:03.94 ^
0:03.94 /home/emilio/src/moz/gecko-2/obj-debug/dist/include/mozmemory_wrap.h:142:41: note: expanded from macro 'realloc_impl'
0:03.94 #define realloc_impl mozmem_malloc_impl(realloc)
Which I really didn't feel like digging into.
* I had to restore the order of TrustOverrideUtils.h and related files in nss
because the .inc files depend on TrustOverrideUtils.h being included earlier.
* I had to add a missing include to RollingNumber.h
* Also had to partially restore include order in JsepSessionImpl.cpp to avoid
some -WError issues due to some static inline functions being defined in a
header but not used in the rest of the compilation unit.
Differential Revision: https://phabricator.services.mozilla.com/D60327
--HG--
extra : moz-landing-system : lando
rg -l 'mozilla/Move.h' | xargs sed -i 's/#include "mozilla\/Move.h"/#include <utility>/g'
Further manual fixups and cleanups to the include order incoming.
Differential Revision: https://phabricator.services.mozilla.com/D60323
--HG--
extra : moz-landing-system : lando
PublishTarget calls Unlock on our LiveSetAutolock.
It's possible for GetInitialInterceptorForIID to fail after this point.
This will cause the failure cleanup code to run, which tries to call Unlock again.
However, the previous call to Unlock set mLiveSet to null, and Unlock previously didn't handle this case.
Now, unlock is a no-op (in release builds) if it's already been called.
MozReview-Commit-ID: 15ffXR6nKqc
--HG--
extra : rebase_source : bf072824f15f5574dd8afbedef82b795086d5fff
If GetInitialInterceptorForIID fails, the live set lock is not released in most cases, but the newly created Interceptor will be destroyed.
The Interceptor's destructor tries to acquire the live set lock again, but that causes a deadlock, since reentry is no longer allowed for a mutex after bug 1364624.
GetInitialInterceptorForIID now ensures the live set lock is always released on failure, thus preventing the deadlock.
MozReview-Commit-ID: z0Q7JLnJXQ
--HG--
extra : amend_source : 0b9837e5500754b5782e72337fc59b7904c5e29c
This was done automatically replacing:
s/mozilla::Move/std::move/
s/ Move(/ std::move(/
s/(Move(/(std::move(/
Removing the 'using mozilla::Move;' lines.
And then with a few manual fixups, see the bug for the split series..
MozReview-Commit-ID: Jxze3adipUh
Because Interceptors disable COM garbage collection to improve performance, they never receive Release calls from remote clients.
If the object can be shut down while clients still hold a reference, this function can be used to force COM to disconnect all remote connections (using CoDisconnectObject) and thus release the associated references to the Interceptor, its target and any objects associated with the HandlerProvider.
A HandlerProvider::DisconnectHandlerRemotes method also had to be added to allow HandlerProviders to disconnect clients for their own objects.
MozReview-Commit-ID: JaxEkOtrP1M
--HG--
extra : rebase_source : bc7a4ab79458eaaddcef8df74ff4d6f685fbfdce
extra : histedit_source : 087f17f09a0c0e1c8e3b5f6d9690f331c15f0b95
COM queries for special interfaces such as IFastRundown when creating a marshaler.
We don't want these being dispatched to the main thread, since this would cause a deadlock on mStdMarshalMutex if the main thread is also querying for IMarshal.
MozReview-Commit-ID: EQcN8Zhewjh
--HG--
extra : rebase_source : 40c39edce139f66fdb43b539b1d6fb0acb00d755
Because Interceptors disable COM garbage collection to improve performance, they never receive Release calls from remote clients.
If the object can be shut down while clients still hold a reference, this function can be used to force COM to disconnect all remote connections (using CoDisconnectObject) and thus release the associated references to the Interceptor, its target and any objects associated with the HandlerProvider.
A HandlerProvider::DisconnectHandlerRemotes method also had to be added to allow HandlerProviders to disconnect clients for their own objects.
MozReview-Commit-ID: JaxEkOtrP1M
--HG--
extra : rebase_source : 2262af8fc3cb1aec8d9c8fc2762f3d61e188cb37
When an object is aggregated, doing a QI to anything other than IUnknown on the inner object AddRefs the outer object.
Thus, before releasing our reference to the inner IUnknown (and thus destroying it), we *must* release any references to interfaces queried from it.
Otherwise, any pointers to interfaces of the inner object would be invalidated.
MozReview-Commit-ID: KXsA8Sagx6G
--HG--
extra : rebase_source : f1dca4ee71f2ed49c8ba19c12862f2b4f9881fca
These conditions are rare and do indicate a problem which breaks accessibility.
However, we aren't getting any closer to diagnosing these as a result of these crashes, so they cause user pain without any gain to us.
MozReview-Commit-ID: D9U4et3Bg7d
--HG--
extra : rebase_source : a81263a0ef97a8ed87129d15ef30ded3005e740c
These conditions are rare and do indicate a problem which breaks accessibility.
However, we aren't getting any closer to diagnosing these as a result of these crashes, so they cause user pain without any gain to us.
MozReview-Commit-ID: D9U4et3Bg7d
--HG--
extra : rebase_source : a81263a0ef97a8ed87129d15ef30ded3005e740c
This fix is completely speculative, but I have strong reason to believe that
we are having lifetime issues, and that refcount stabilization might be coming
into play.
The situation is this:
Suppose we're aggregating an object, so we pass |this| as the outer IUnknown.
The inner object might perform AddRef() and Release() on |this| during its
initialization.
But if we're in the process of creating the outer object, that refcount might
not yet have been incremented by 1, so the inner object's invocation of the
outer object's Release() could trigger a deletion.
The way around this is to temporarily bump the refcount when aggregating another
object. The key, though, is to not do this via AddRef() and Release(), but by
direct maniuplation of the refcount variable, so that we don't trigger any of
the self-deletion stuff.
MozReview-Commit-ID: 3WA2AJvb6jY
--HG--
extra : rebase_source : ab05a52760541a4ab11f1245a5ddeae938998047
This patch adds two additional fields to each mscom log entry: The first is
the duration, in microseconds, of time spent in mscom overhead when executing
a call from the MTA on behalf of a remote client.
The second field is the duration, in microseconds, of time spent actually
executing the method within Gecko itself.
(In other words, the sum of the two fields will equal the total duration of
time spent executing the call.)
MozReview-Commit-ID: EhFieEPrhE5
